CALCHDMSTR - CALET CHarge Detector (CHD) Master Catalog

Overview

The CALCHDMSTR database table records high-level information of the particle rates obtained with the CHarge Detector (CHD), the top layer of the calorimeter instrument on the CALorimetric Electron Telescope (CALET) mission.

CALET is a Japanese mission led by JAXA, in collaboration with the Italian Space Agency (ASI) and NASA, and is dedicated to the study of high energy cosmic rays. CALET was launched on August 19, 2015, by a Japanese carrier, H2 Transfer Vehicle, and robotically installed on the Japanese Experiment Module-Exposed Facility (JEM-EF) on the International Space Station (ISS). CALET started scientific observations in October, 2015.

Catalog Bibcode

2018APh...100...29A

Bulletin

The CALCHDMSTR database table was last updated on 30 December 2025.

References

On-orbit operations and offline data processing of CALET onboard the ISS.
    Asaoka Y. et al., 2018, Astrophysical Particle, 100 29a
   =2018APh...100...29A

Provenance

The CALET CHD particle rates as function of time are delivered by the CALET team in Japan as ASCII files to the DARTS archive located at ISAS (Japan). The HEASARC developed software to create the FITS version of these time-particle rate files. The software is run at DARTS, and the output is placed online at https://darts.isas.jaxa.jp/astro/calet/. The HEASARC hosts a copy of these files and generates this database table by collecting high-level information from the data. The Data and the database table are updated regularly during operation.

Description

The CALET mission is comprised of two detectors: the calorimeter (named CALET) and the Gamma Ray Burst Monitor (Tori S. and CALET Collaboration, 2017, ICRC, 35, 1092).

The CALET detector consists of a CHarge Detector (CHD), which identifies the charge of the incident particle in an IMaging Calorimeter (IMC). The IMC reconstructs the track of the incident particle and finely images the initial shower development, and a Total AbSorption Calorimeter (TASC), which absorbs the entire energy of the incoming particle and identifies the particle species using hodoscopic scintillator arrays. The calorimeter directly measures the cosmic ray electron spectrum in the energy range of 1 GeV to 20 TeV.

The CHD is double-layered (X, Y), placed at the top, above the IMC detector. The signals from the X and Y layers are integrated over 1 second and used to create a file with 1-day of rates associated with this database table.

Each row of the database table corresponds to a specific day and has an associated one file. Each record also includes the minimum, maximum, and average of the rates within 1-day observation.

Parameters

ObsID
This parameter contains a unique row identifier for the database table. It is a 8-digit number, YYYYMMDD, representing the year, month and day of the file with the particle rates. It is also used to name the files.

Time
The start time of the file. The data have been divided into 1-day observations. This time corresponds to the start of the day.

End_Time
The end time of the file. The data have been divided into 1-day observations. This time corresponds to the end of the day.

Exposure
This parameter corresponds to the total effective exposure recorded in the 1-day time interval of the data included in the file.

Processing_Date
This parameter records the date when the data were last processed.

Processing_Version
This records the version of the processing script used in the pipeline to generate the data products for the observation.

Rate_Mean
Records the mean value of the particle rate in the 1-day observation.

Rate_Min
Records the minimum value of the particle rate in the 1-day observation.

Rate_Max
Records the maximum value of the particle rate in the 1-day observation.

Contact Person

Questions regarding the CALCHDMSTR database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Thursday, 07-Aug-2025 14:00:44 EDT